DescriptionTheory of Mind (ToM) is the ability to interpret the behavior of others in terms of underlying mental states such as beliefs, wants, desires (Premack and Woodruff, 1978). The simulation theory of ToM claims that an individual replicates, or mirrors, the assumed mental states of a target individual and processes them using his/her own mental architecture--the same architecture that is used to make decisions based on one's own beliefs, desires, or thoughts. Thus, ToM may be considered as a form of empathy, a process where the perception of a target’s state generates a state in the observer that is more applicable to the target’s situation than to the subject’s own prior situation (Preston and de Waal, 2002). The experience of emotional empathy is influenced by coalitional cues such as familiarity (Liew, Han, and Aziz-Zadeh, 2011), similarity (Xu, Zuo, Wang, and Han, 2009), and shared group membership (Avenanti, Sirigu, and Aglioti, 2010), as well as immediate situational cues such as the color of a target's tee shirt (Kurzban, Tooby, and Cosmides, 2001), or simply referring to a counterpart in a task as a partner or opponent (Burnham, McCabe, and Smith, 2000). To date, the effect of such immediate coalitional cues has not been tested for ToM. In the present study, a ToM task was designed to test subjects' perspective taking ability in response to one of three different conditions, a neutral frame, a cooperative frame, or a competitive frame. Two types of perspective-taking errors were recorded: incorrect responses and response hesitations. It was predicted that subjects would 1) make significantly fewer errors on the task in the cooperative frame relative to the other two conditions, and 2) make significantly more errors in the competitive condition. Partial support of these predictions was found. ToM was sensitive to cues of coalition, but only for one type of error, hesitations. While cooperative and competitive conditions were marginally significantly different from each other in the expected direction (subjects in the cooperative frame made fewer perspective taking errors than subjects in the competitive frame), neither differed significantly from the control condition.